Macracanthorhynchus spp.

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This page quotes a published document. Everything below in quotation marks is copied word for word from https://capcvet.org/guidelines/macracanthorhynchus-spp/, published by CAPC and retrieved on 2026-09-16. The quotations are excerpts; the document itself is linked and is the authority. Nothing has been reworded.

This page quotes the Companion Animal Parasite Council guideline for Macracanthorhynchus spp., section by section: the opening sentences of 8 sections, copied without change and linked to the guideline, which was retrieved on 2026-09-16. The guideline itself is the authority and carries the full text.

The guideline

Companion Animal Parasite Council, Macracanthorhynchus spp., at https://capcvet.org/guidelines/thorny-headed-worm/. Retrieved 2026-09-16. Each heading below is the guideline’s own, and the quotation under it is how that section begins. The full section, and the species tabs where the guideline gives them, are on the linked page.

Synopsis

CAPC Recommends Reduce the risk of infection of acanthocephalans by limiting ingestion of insects, primarily beetles or millipedes. Macracanthorhynchus ingens and M. hirudinaceus are potentially zoonotic, and young children in particular should be monitored and kept from ingesting insects.

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Species

Canine Macracanthorhynchus ingens Macracanthorhynchus hirudinaceus Macracanthorhynchus ingens Adult Macracanthorhynchus ingens egg (88 x 60um; 400x)

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Disease

Infections with M. hirudinaceus have not yet been associated with clinical disease in dogs. However, treatment is still warranted due to the possibility of zoonotic disease associated with this helminth.

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Prevalence

Macracanthorhynchus hirudinaceus has been reported in a broad range of locations, including North America, Asia, and the Middle East. Infections of M. ingens has been reported in North American dogs exposed to intermediate hosts.

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Diagnosis

Observation of eggs on fecal flotation, or more commonly fecal sedimentation. Adult worms found in feces of the definitive host.

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Treatment

There is no approved treatment of M. hirudinaceus in dogs, although ivermectin and lefluronomide have been used in the treatment of swine. At a concentration of 100ug/kg per day in medicated feed, efficacy of ivermectin was 100% in swine.

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Control and Prevention

Prevent ingestion of the beetle or millipede intermediate hosts, especially in areas populated by wild or domestic swine and other wildlife vectors.

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Public Health Considerations

Human infection by M. hirudinaceus and M. ingens have been reported in cases where accidental or intentional consumption of the intermediate host (insect) occurred.

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Sources

  • capc-thorny-headed-wormCAPC · retrieved 2026-09-16
    CAPC Recommends Reduce the risk of infection of acanthocephalans by limiting ingestion of insects, primarily beetles or millipedes. Macracanthorhynchus ingens and M. hirudinaceus are potentially (Synopsis)

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